Method and apparatus for arc welding with arc control

ABSTRACT

A method and apparatus for providing welding power with an arc-width control is disclosed. The power supply includes a power circuit that provides a welding output characterized by a plurality of welding output parameters, and the power circuit receives at least one control input. A controller provides control signals to the power circuit. The controller receives user inputs for arc width and wire feed speed. The controller has an arc width control module that provides control signals that adjust one or more welding output parameters. The adjustment has a gain responsive to the wire feed speed input, such that there are at least three gains over a range of possible wire feed speeds, in one embodiment. The arc width control module provides control signals that adjust at least five welding output parameters in response to the wire feed speed input and the arc-width control input, in another embodiment.

FIELD OF THE INVENTION

The present invention relates generally to the art of arc welding. Morespecifically, it relates to arc welding with control of arc parameters.

BACKGROUND OF THE INVENTION

Electric arc welding is well known, and is performed with a variety ofprocesses using a variety of types of equipment. One electric arcwelding process is a pulse spray process, which is typically performedusing a wire feeder and a power supply. An example of a prior art powersupply used in pulse spray welding is a Miller S64M™ wire feeder. TheMiller S64M™ wire feeder may be used with a Miller XMT304™ power supply.

Typically, in pulse spray processes, power is provided from the powersupply to the wire feeder, and the wire feeder provides the wire andpower to the arc. The wire feeder typically includes a controller, whichmay be part of or separate from the wire feeder, and which controls thewire feed speed based on a user-selected input. Additionally, thecontroller provides a command signal to the power supply which causesthe power supply to output a current and voltage at a desired magnitude.The command is produced at least in response to a user-selected wirefeed speed. The current amplitude is often controlled as a function oftime, switching between a background current and a peak current, thuscreating a pulsed output.

The welding process is often controlled by controlling various weldingparameters. For example, the pulse spray process is typically controlledby controlling such welding parameters as peak amps, background amps,pulse width, voltage, ramps, and frequency. The parameters are typicallycontrolled using a controller which provides control signals to the wirefeeder (or power supply). Some welding power supplies control the rampup and ramp down (transition from background to peak, or peak tobackground). Also some welding power supplies provide an adaptive outputvoltage where the voltage is controlled to provide a desired or constantarc length. As used herein, welding parameters refer to parameters ofthe welding power output, such as peak amps, background amps, frequency,pulse width, voltage (constant or adaptive) ramp up, and ramp down.Adaptive voltage, or adaptive arc length, as used herein includesadjusting (changing or scaling) an output parameter, pulse frequencymodulation for example, to maintain a constant or desired arc length.Because these welding parameters are used to control the output it maybe said that the output is characterized by a plurality of outputparameters.

Some wire feeder controllers include factory programs which presetvarious welding parameters. The values for these parameters are storedby the controller (often in digital or other types of memory). Also,many controllers allow the user to store user-created programs whichstore user-selected welding parameters. In such a case, the user teachesor sets the desired values for welding parameters, and stores them inthe memory.

When the user wishes to access either the factory preset or theuser-created programs, they are individually selected using some type ofdigital interface. Then, the controller commands the power supply toprovide power at the called for current, peak current, backgroundcurrent, frequency, ramps and pulse width, thus providing the desiredwelding parameters.

Different types of welding require different types of arccharacteristics (such as the plasma cone angle\width and intensity,hereafter referred to as arc width). For example, flat, horizontal down,welding typically may be performed using a relatively wide arc.Conversely, overhead welding, or welding in other difficult orinconvenient physical positions, often requires a narrow arc.

The preset factory programs are typically set to provide for weldingwith a wide arc, since this is the one most inexperienced welders willuse. To access the narrower arc the welder must adjust the weldingparameters manually and individually until the desired arc is obtained.It may be necessary to decrease one parameter as another parameter isincreased, without changing other arc characteristics. Without changingother arc characteristics, as used herein, refers to not changing an arccharacteristic from the standpoint of the user and/or in such a way thearc is adversely affected, such as not changing arc length to the extentthe weld is adversely affected or the user notices the change.

However, many welders lack the experience to know how to properly adjustthe various parameters, and in particular welders do not understand theinteraction between adjusting various parameters. For example, todecrease arc width, frequency is increased. However, increasingfrequency also increases arc length. Many welders do not know this, nordo they know how to adjust the other welding parameters to offset theeffect of changing frequency on arc length.

Some prior art systems provide for the user to automatically adjust arcwidth. As described in U.S. Pat. No. 6,121,575 (owned by the assignee ofthe present invention), the system adjusts welding parameters with asingle knob (i.e. a single arc control input) that controls arc width(or a different arc characteristic) without adversely affecting someother arc characteristics. Specifically, the arc width adjustment ismade by adjusting three or four welding parameters simultaneously, suchthat one or more other characteristics of the arc are minimallyaffected. Simultaneous, in this context, means at the same time from thestandpoint of the user and the welding process. They might occur oneafter the other, but so far as the user observes by watching the weldingprocess, they occur at the same time.

A single digital knob (or other input device such as a digital inputpanel, keyboard, analog knob, sliding switch, etc) on the controllerallows the user to select between an arc width adjustment of 0 and 20.An arc width adjustment of 0 is no arc width adjustment, and an arcwidth adjustment of 20 is the maximum arc width adjustment (narrow arccone) in the preferred embodiment. No adjustment is having theparameters be as they were in the original program, which is typicallybest for flat, horizontal down, welding (i.e., using a wide arc).

While the system described in U.S. Pat. No. 6,121,575 is a considerableadvance over the prior art, it only controls three or four parameters,and does not control adaptive arc length (output voltage) in response tothe arc width setting. Thus, when changing arc width the arc lengthother characteristics may remain constant in some circumstances, butunder other circumstances changing the arc width will also change thearc length. Also, that system provided two gains, one for over wire feedspeeds of more than 225 IPM, and one for less than 225 IPM. This causeda step change from above and below 225 IPM, which was noticeable at thearc.

Accordingly, it is desirable that a welding power supply and wire feederinclude a controller that allows the user to adjust the arc width usinga single knob, such that more five or more welding parameters,preferably including arc voltage, are adjusted to obtain a desired arcwidth, while maintaining one or more other characteristics of the arc,preferably including arc length.

SUMMARY OF THE PRESENT INVENTION

According to a first aspect of the invention a welding power supply hasan arc-width control. The power supply includes a power circuit thatprovides a welding output characterized by a plurality of welding outputparameters, and the power circuit receives at least one control input. Acontroller provides control signals to the power circuit. The controllerreceives user inputs for arc width and wire feed speed. The controllerhas an arc width control module that provides control signals thatadjust one or more welding output parameters. The adjustment has a gainresponsive to the wire feed speed input, such that there are at leastthree gains over a range of possible wire feed speeds.

According to a second aspect of the invention the welding power supplywith arc-width control includes a power circuit that provides a weldingoutput characterized by at least five welding output parameters, and thepower circuit receives at least one control input. A controller providescontrol signals to the power circuit. The controller receives userinputs for arc width and wire feed speed. The controller has an arcwidth control module that provides control signals that adjust at leastfive welding output parameters in response to the wire feed speed inputand the arc-width control input.

According to a third aspect of the invention a welding power supplyincludes a source of power with at least one power source control input.A wire feeder is connected to the source of power and has at least onewire feeder control input. A controller has welding parameter outputsconnected to the power source control input and the wire feeder controlinput. The controller also has an arc width input, and at least fivewelding parameters are simultaneously controlled in response to the arcwidth input such that a desired arc width is obtained, without changingother arc characteristics.

The adjustment gain varies over the entire range of possible wire feedspeeds in accordance with one embodiment of the invention.

The adjustment gains have at least three taught points for a given wirefeed speed in other embodiments, and the gains may be interpolatedbetween the at least three taught points.

The plurality of welding output parameters include peak amps, backgroundamps, pulse width, frequency, adaptive voltage, ramp up and ramp down,and the adjustment includes adjustments for at least three, five, six ormore of the parameters in other embodiments.

Other principal features and advantages of the invention will becomeapparent to those skilled in the art upon review of the followingdrawings, the detailed description and the appended claims.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a waveform of a typical welding output for a pulsed arcwelding process such as that used in the present invention;

FIG. 2 is a flow chart of a program or a subroutine used to implementone embodiment of the present invention; and

FIG. 3 is a block diagram of the preferred embodiment of the presentinvention.

Before explaining at least one embodiment of the invention in detail itis to be understood that the invention is not limited in its applicationto the details of construction and the arrangement of the components setforth in the following description or illustrated in the drawings. Theinvention is capable of other embodiments or of being practiced orcarried out in various ways. Also, it is to be understood that thephraseology and terminology employed herein is for the purpose ofdescription and should not be regarded as limiting. Like referencenumerals are used to indicate like components.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

While the present invention will be illustrated with reference to aparticular implementation and a particular flow chart for use with aparticular power supply and wire feeder, it should be understood at theoutset that the invention may also be employed with other flow charts,routines, values, limits, parameters, and equipment.

The invention generally includes adjusting welding parameters with asingle input (i.e. a single arc width control input) that controls arcwidth without adversely affecting other arc characteristics, such as arclength, i.e., arc width control. (Power and/or deposition rate do notchange in alternative embodiments.) For example, in the preferredembodiment a single digital input (such as a digital input panel,digital knob, keyboard, analog knob, sliding switch, etc) on thecontroller allows the user to select between an arc width adjustment of0 and 50. An arc width setting of 25 is no arc width adjustment, an arcwidth setting of 0 provides the maximum arc width, and an arc widthadjustment of 50 is the minimum arc width in the preferred embodiment.No adjustment is having the parameters be as they were in the originalprogram, which is typically best for flat, horizontal, welding.

The preferred embodiment uses a wire feeder design similar to the MillerS64M™ wire feeder, and a power supply design similar to the MillerXMT304™ power supply, but packaged in a single housing, or the MM251™ ora system such as that described in U.S. Pat. No. 6,107,602. Thepreferred wire feeder includes a digital controller, which includes amicroprocessor and an memory. The controller, as described above, setswelding parameters according to factory set, or in an alternativeembodiment, user-set, programs. Alternative embodiments provide that thecontroller is part of the power supply, or in a separate housing. Thecontroller also receives as a user set input the arc width adjustmentknob (or other input device) setting in the preferred embodiment. A userset input can be from an individual or an automated system. This inputis used to scale (i.e. change from the previous setting) the programwelding parameter settings, as detailed below, to adjust the arc widthfrom a minimum to a maximum. The knob setting is stored with the otherweld parameter settings in any user-created programs.

The arc width adjustment is made by adjusting five or more weldingparameters simultaneously, such that other characteristics of the arc,such as arc length, are minimally affected. The inventor has determinedvarious percentage adjustments of these parameters which is believed toadequately satisfy these objectives given the equipment used in thepreferred embodiment, but other adjustments may be made, and theinvention is not limited to the specific adjustments detailed below.

Referring now to FIG. 1 a typical wave form of a pulse spray weldingprocess is shown. The wave form includes a background amperage level BAand peak amperage level of P_(A), pulse width P_(W) and period (1/f or1/frequency). Also shown is the ramp up from background to peak and rampdown from peak to background. Output voltage is not shown, and isgenerally held constant for a constant arc length, or is adaptivelycontrolled (such as by known adaptive voltage control, which can usepeak voltage). Adaptive control, in at least one known scheme, works bymodulating the pulse frequency to produce a desired arc voltage, andthus a desired arc length.

Five welding parameters: peak amps, background amps, pulse width,frequency and adaptive voltage (arc length) are adjusted according tothe preferred embodiment of the present invention (or six, seven or moreare adjusted according to one alternative) such that when the useradjusts the arc width one or more other arc characteristics are notchanged or adversely affected.

For example, a decrease in arc width is obtained by increasingfrequency. If only the frequency is changed, the arc length willincrease. The present invention also adjusts background amps and pulsewidth, peak amps, and adaptive voltage/arc length. The magnitudes of thechanges are selected to offset the increase in arc length caused by thefrequency increase, resulting in a no, or little, net change in arclength. Adjusting adaptive arc voltage/length control in the presentinvention can be implemented by adjusting both the nominal frequency(the frequency without adaptive voltage control), and adjusting thefrequency modulation (i.e., adaptive voltage) of the adjusted nominalfrequency.

Each of the parameters are set by a program (a factory program oruser-defined program) implemented by the wire feeder microprocessor (oranalog control circuitry in an alternative embodiment). The preferredembodiment adjusts those parameters as set forth below. The specificadjustments of the preferred embodiment were determined using empiricaldata, and may be different in different alternatives. Thus, a decreasedbackground amps, and a decreased pulse width. Proper adjustment of theseparameters will also result in a relatively unchanged arc length. Thisis especially useful when welding in physically inconvenient positions.

FIG. 2 is a flow chart showing a routine which implements one embodimentof the present invention. The flow chart is implemented with a routinein the controller for the wire feeder. The routine may be accessed on anongoing basis, or when the welding process is initiated. Theuser-selected arc control is determined in a box 201. This is the inputused to scale the welding parameters to change the arc width, withoutadversely affecting one or more other arc characteristics. The preferredembodiment uses a scalar value of between 0 and 50 for the arc widthsetting, for the adjustments that provide the widest and narrowest arcwidth. A setting of 25 provides no adjustment to the arc width.

The controller has a number of taught points. Preferably, separatetaught points are provided for a number of different common materials,wire size and gas type. Pulse welding systems have various programs forcommon materials. According to the preferred embodiment taught pointsare provided for some or all of these programs, such as for 0.035 steel,0.045 steel, 0.035 A1 4043, 0.047 A1 4043, 0.035 A1 5356, 0.047 A1 5356,0.035 stainless and 0.045 stainless.

Taught points for a given material are provided for a number of wirefeed speeds, and for at least 3 arc width settings in the preferredembodiment. (Taught point refers to setting parameters for one arc widthsetting at one wire feed speed). For example, in the preferredembodiment there are 8 wire feed speeds having three arc width taughtpoints each, for a total of 24 taught points, for 0.035 steel. The arcwidth settings for which taught points are provided are 0, 25 and 50. Itshould be noted that the taught point of 25 corresponds to no adjustmentfor arc width. Therefore 8 of the 24 taught points are no adjustment.Each taught point has a gain for each parameter being adjusted. Thus, inthe preferred embodiment each taught point has 5 gains stored in memory.Each gain is used to change, by a percentage, the nominal settings forits respective parameter. Gains are interpolated between arc widthsettings and between wire feed speed settings. The tables below showtaught points for 0.045 stainless steel at an arc width setting of 0 and50. The data is percentage change of various parameters, and since anarc width setting of 25 corresponds to no arc width adjustment, allgains are zero for the taught points for an arc width setting of 25.Gain, as used herein in conjunction with arc width control, refers tochanging the nominal setting of an output parameter in response to anarc width setting.

ARC WIDTH SETTING = 0 wfs Adapt V Peak Amp Back Amp Freq Pw 50 0.0 −11.320.0 −21.9 35.0 100 −1.8 −12.7 22.2 −10.3 23.5 125 −6.2 −9.1 20.0 −19.035.3 175 1.0 −8.1 18.5 −22.6 37.5 225 3.3 −4.4 20.0 −23.1 38.1 325 3.3−8.6 17.8 −22.7 36.4 425 0.0 −6.9 45.5 −24.5 40.4 500 0.9 −6.7 16.7−22.1 36.0

ARC WIDTH SETTING = 50 wfs Adapt V Peak A Back A Freq Pw 50 −9.1 21.0−20.0 12.5 −27.5 100 −8.9 19.7 −16.7 11.8 −30.0 125 −4.1 21.2 −32.0 22.8−23.7 175 −9.5 22.4 −47.7 24.5 −27.5 225 −11.6 32.9 −62.7 34.6 −34.3 325−12.9 30.0 −66.7 36.9 −36.4 425 −12.5 30.6 −68.2 17.0 −36.2 500 −12.326.7 −70.0 26.8 −38.0

The number of taught points is chosen to provide a smooth change overboth arc widths and wire feed speeds. The gain, or data, for each taughtpoint was empirically determined by observing the arc. Other taughtpoints are obtained in a similar manner. The specific gains shown aboveare subjective and other gains may be adequate as well. Implementationof this invention is properly done by empirically determining gains forthe particular system used to implement this invention.

Referring again to FIG. 2, after determining the arc width setting, thepeak amps are adjusted 202 and the background amps are adjusted at 205.The frequency is adjusted at 206 and the pulse width is adjusted at 208.The adaptive voltage (frequency modulation in the preferred embodiment)is adjusted at 210, and in various embodiments the ramp up and ramp downare adjusted at 212. The ramp up and ramp down are not adjusted in thepreferred embodiment. The adjustments are made for the given wire feedspeed, and the gain or new weld parameters are interpolated from botharc width setting and wire feed speed.

The actual code used to implement the invention need not be described,since any number of routines can accomplish the interpolations. It is alinear interpolation in the preferred embodiment, but otherinterpolations are also contemplated. By interpolating over wire feedspeeds the gains vary over the entire range (between the max and minwire feed speeds) of possible wire feed speeds.

While there are many ways of determining output parameters in accordancewith this invention, the following examples show one manner of doing so.Using the tables above for 0.045 stainless steel, and looking atbackground amps, if the set points are a WFS (wire feed speed) of 425inches per minute (IPM) and an arc width setting of 12, the percentagemay be interpolated to be (12)/25)*45.5=21.8. Thus, background amps areadjusted upward by 21.8 percent for an arc width setting of 12 at a WFSof 425.

When the WFS is between taught wire feed speed points, then anotherinterpolation is performed. For example, given a WFS of 400 IPM and anarc width setting of 12, in addition to the calculation above, theadjustment may be calculated at a WFS of 325 and an arc width of 12, or(12/25)*17.8=8.5 percentage adjustment. Then, the adjustment isinterpolated between the two speeds,(400−325/(425−325)*(21.8−8.5)+8.5=18.5% upward adjustment.

Another way of preforming the interpolation, is to first interpolatebetween wire feed speeds, and then between arc width settings. For thesettings above (WFS of 400, arc width of 12), the interpolation betweenWFS=425 and WFS=325 for an arc width of 0 gives(400−325)/(425−325)*(45.5−17.8)+17.8=38.6. Then interpolating to an arcwidth setting of 12, the result is (12/25)*38.6=18.5.

It may be seen that either manner yields the same result. Other types ofinterpolation will provide different results, and many routines may beused to perform the calculations.

Referring now to FIG. 3, a block diagram of a welding system 300 made inaccordance with the preferred embodiment includes a controller 302, awire feeder 303 and a power source 304 that cooperate to provide an arc306. Controller 302 receives two user inputs, one for wire feed speedand one for arc width. These inputs are provided to an arc width controlmodule 307 which adjusts output parameters using a welding parameteradjustment output, as set forth above to control the arc width inresponse to the arc width setting. Controller, as used herein, includesdigital and analog circuitry, discrete or integrated circuitry,microprocessors, DSPs, etc., and software, hardware and firmware,located on one or more boards, used to control a device such as a powersupply or power source. Module, as used herein, includes software and/orhardware that cooperates to perform one or more tasks, and can includedigital commands, power circuitry, networking hardware, etc.

Controller 302 provides control outputs which are a control inputs topower source 304 in response to the program therein, as adjusted by thearc control module. Power source, or source of power, as used herein,includes the power circuitry such as rectifiers, switches, transformers,SCRs, etc. that process and provide the output power. Control input, asused herein, includes an input used to control a power supply, such as aset point, gate signals, phase control signals, etc. Control output, asused herein, includes an output used to control a circuit, such as asetpoint, switch signals, gate signals, phase control signals, etc.

Numerous modifications may be made to the present invention which stillfall within the intended scope hereof. Thus, it should be apparent thatthere has been provided in accordance with the present invention amethod and apparatus for controlling a welding process that fullysatisfies the objectives and advantages set forth above. Although theinvention has been described in conjunction with specific embodimentsthereof, it is evident that many alternatives, modifications andvariations will be apparent to those skilled in the art. Accordingly, itis intended to embrace all such alternatives, modifications andvariations that fall within the spirit and broad scope of the appendedclaims.

1. A welding power supply having an arcwidth control, comprising: apower circuit having a welding output and at least one control input,wherein the welding output is characterized by a plurality of outputwelding parameters; and a controller, having at least one controloutput, connected to the at least one control input, and having a useradjustable arc-width control input, and a user adjustable wire feedspeed input, wherein the controller includes an arc width control modulehaving as inputs the wire feed speed input and the arc width controlinput, and having at least one welding parameter adjustment output, andwherein the at least one welding parameter adjustment output has a gainresponsive to the wire feed speed input, such that the gain varies overthe entire range of possible wire feed speeds.
 2. The welding powersupply of claim 1, wherein the at least one welding parameter adjustmentoutput gains have at least three taught points for a given wire feedspeed.
 3. The welding power supply of claim 2, wherein the weldingparameter adjustment output gains are interpolated between the at leastthree taught points.
 4. The welding powor supply of claim 1, wherein theplurality of output welding parameters include peak amps, backgroundamps, pulse width, frequency, adaptive voltage, ramp up and ramp down,and the at least one welding parameter adjustment includes adjustmentsfor at least three of the plurality of output parameters.
 5. The weldingpowor supply of claim 4, wherein the at least one welding parameteradjustment includes adjustments for at least five of the plurality ofoutput parameters.
 6. The welding pownr supply of claim 5, wherein theat least one welding parameter adjustment includes adjustments for atleast six of the plurality of output parameters.
 7. A welding powersupply having en arc-width control, comprising: a power circuit having aweldinq output and at least one control input, wherein the weldingoutput is characterized by at least five output parameters: and acontroller, having at least one control output, connected to the atleast one control input, and having a user adjustable arcwidth controlinput, and a user adjustable wire feed speed input, wherein thecontroller includes an arc width control module having as inputs thewire feed speed input and the arc width control input, and having atleast five welding parameter adjustment outputs that are responsive tothe wire feed speed input and the arc-width control input.
 8. Thewelding power supply of claim 7, wherein the at least five weldingparameter adjustment outputs have gains responsive to the wire feedspeed input, wherein the gains vary over the entire range of possiblewire feed speeds.
 9. The welding power supply of claim 8, wherein the atleast five welding parameter adjustment output gains has at least threetaught points for a given wire feed speed.
 10. The welding power supplyof claim 9, wherein the at least five welding parameter adjustmentoutput gains are interpolated between the at least three taught points.11. The welding power supply of claim 8, wherein the at least fiveoutput parameters include peak amps, background amps, pulse width,frequency, and adaptive voltage, and the at least five welding parameteradjustment outputs includes adjustments for peak amps, background amps,pulse width, frequency, and adaptive voltage.
 12. The welding powersupply of claim 11, wherein the at least five output parameters furtherinclude ramp up and ramp down, and the at least five widding parameteradjustment outputs further include adjustments for ramp up and rampdown.
 13. A welding power supply comprising: a source of power, havingat least one power source control input; a wire feeder, connected to thesource of power and having at least one wire feeder contrul input; and acontroller having welding parameter outputs connected to the powersource control input and the wire feeder control input, and furtherincluding an arc width input, wherein at least five welding parametersare simultaneously controlled in response to the arc width input suchthat a desired arc width is obtained, without changing other arccharacteristics.
 14. The welding supply of claim 13 wherein the at leastfive welding parameters include at least five of peak amps, backgroundamps, pulse width, pulse frequency, adaptive voltage, ramp up and rampdown.
 15. A welding power supply having an arc-width control,comprising: power means for providing a welding output in response to atleast one control input, wherein the welding output is characterized bya plurality of output welding parameters; and control means forcontrolling the power means with at least one control output connectedto the at least one control in response to a user adjustable arc-widthcontrol input and a user adjustable wire feed speed input, wherein thecontrol means includes an arc width control means for controlling arcwidth, and having as inputs the wire feed speed input and the arc-widthcontrol input, and having at least one welding parameter adjustmentoutput, and wherein the at least one welding parameter adjustment outputhas a gain responsive to the wire feed speed input, wherein the controlmeans includes means for receiving at least three taught points for agiven wire feed speed and further including means for interpolating thewelding parameter adjustment output gains between the at least threetaught points.
 16. The welding power supply of claim 15, wherein the atleast one welding parameter adjustment output gain varies over theentire range of possible wire feed speeds.
 17. The welding power supplyof claim 15, wherein the plurality of output parameters include peakamps, background amps, pulse width, frequency, adaptive voltage, ramp upand ramp down, and the at leant one welding parameter adjustmentincludes adjustments for at least three of the plurality of outputparameters.
 18. The weldinq power supply of claim 17, wherein the atleast one welding parameter adjustment includes adjustments for at leastfive of the plurality of output parameters.
 19. The welding power supplyof claim 18, wherein the at least one welding parameter adjustmentincludes adjustments for at least six of the plurality of outputparameters.
 20. A welding power supply having an arc-width control,comprising: power means for providing a welding output in response to atleast one control input, wherein the welding output is characterized byat least five output parameters; and control means for controlling thepower means with at least one control output connected to the at leastone control input in response to a user adjustable arc-width controlinput and a user adjustable wire feed speed input, and for providing atleast five welding parameter adjustment outputs that are responsive tothe wire feed speed input and the arc-width control input.
 21. Thewelding power supply of claim 20, wherein the at least five weldingparameter adjustment outputs have gains responsive to the wire feedspeed input, wherein the gains vary over the entire range of possiblewire feed speeds.
 22. The welding power supply of claim 21, wherein theat least five welding parameter adjustment output gains has at leastthree taught points for a given wire feed speed.
 23. The welding powersupply of claim 22, wherein the at least five welding parameteradjustment output gains are interpolated between the at least threetaught points.
 24. The welding power supply of claim 23, wherein the atleast five output parameters include peak amps, background amps, pulsewidth, frequency, and adaptive voltage, and the at least five weldingparameter adjustment outputs includes adjustments for peak amps,background amps, pulse width, frequency, and adaptive voltage.
 25. Thewelding power supply of claim 22, wherein the at least five outputparameters further include ramp up and ramp down, and the at least fivewelding parameter adjustment outputs includes further includeadjustments for ramp up and ramp down.
 26. A welding power supplycomprising: power means for providing welding power in response to atleast one power source control input; wire feeding means, connected tcathe source of power, for feeding wire in response to at least one wirefeeder control input; and control means for providing welding parameteroutputs, connected to the power source control input and the wire feedercontrol input, and further including an arc width input, and further forsimultaneously controlling at least five welding parameters are inresponse to the arc width input such that a desired arc width isobtained, without changing other arc characteristics.
 27. The weldingsupply of claim 26, wherein the at least five welding parameters includeat least five of peak amps, background amps current, pulse width, pulsefrequency, adaptive voltage, ramp up and ramp down.
 28. A method ofproviding welding power, comprising: providing welding power, whereinthe power is characterized by a plurality of output parameters; andcontrolling the power, and the plurality of output parameters, inresponse to a user adjustable output set point; and controlling arcwidth and the user adjustable set point in response to a user adjustablearc-width control input, by adjusting the plurality of output parameterswith a gain, wherein the gain varies over the entire range of possibleuser adjustable output set points.
 29. The method of claim 28, whereinthe user adjustable output set point is a wire feed speed setting. 30.The method of claim 28, wherein the gains have at least three taughtpoints for a given wire feed speed.
 31. The method of claim 30, whereinthe gains are interpolated between the at least three taught points. 32.The method of claim 28, wherein the plurality of output parametersinclude peak amps, background amps, pulse width, frequency, adaptivevoltage, ramp up and ramp down, and the adjusting includes adjusting atleast three of the plurality of output parameters.
 33. The method ofclaim 32, wherein the adjusting includes adjusting at least five of theplurality of output parameters.
 34. The method of claim 32, wherein theadjusting includes adjusting at least six of the plurality of outputparameters.
 35. A method of arc welding, comprising: providing weldingpower in response to at least one control input, wherein the weldingpower is characterized by at least five output parameters; andcontrolling the power in response to a user adjustable arcwidth controlinput and a user adjustable wire feed speed input by adjusting the atleast five parameters in response to the wire feed speed input and thearc-width control input.
 36. The method of claim 35, wherein the atleast five welding parameter adjustments have gains responsive to thewire feed speed input, wherein the gains vary over the entire range ofpossible wire feed speeds.
 37. The method of claim 35, wherein the atleast five welding parameter adjustment output gains have at least threetaught points.
 38. The method of claim 37, wherein the at least fivewelding parameter adjustment output gains are interpolated between theat least three taught points.
 39. The method of claim 35, wherein the atleast five welding parameter adjustment output gains have at least threetaught points.
 40. The method of claim 39, wherein the at least fiveoutput parameters further includeramp up and ramp down, and the at leastfive welding parameter adjustment outputs includes further includeadjustments for ramp up and ramp down.
 41. A method of providing weldingpower comprising: feeding wire to a weld; providing power to the weld;and controlling output parameter of the power and the speed of feedingwire in response to a user adjustable arc width input, wherein at leastfive output parameters are simultaneously controlled in response to thearc width input such that a desired arc width is obtained, withoutchanging other arc characteristics.
 42. The method of claim 41 whereinthe at least five welding parameters include at least five of peak amps,background amps current, pulse width, pulse frequency, adaptive voltage,ramp up and ramp down.